michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef nsAlgorithm_h___
michael@0: #define nsAlgorithm_h___
michael@0: 
michael@0: #include "nsCharTraits.h"  // for |nsCharSourceTraits|, |nsCharSinkTraits|
michael@0: 
michael@0: template <class T>
michael@0: inline
michael@0: T
michael@0: NS_ROUNDUP( const T& a, const T& b )
michael@0:   {
michael@0:     return ((a + (b - 1)) / b) * b;
michael@0:   }
michael@0: 
michael@0: // We use these instead of std::min/max because we can't include the algorithm
michael@0: // header in all of XPCOM because the stl wrappers will error out when included
michael@0: // in parts of XPCOM. These functions should never be used outside of XPCOM.
michael@0: template <class T>
michael@0: inline
michael@0: const T&
michael@0: XPCOM_MIN( const T& a, const T& b )
michael@0:   {
michael@0:     return b < a ? b : a;
michael@0:   }
michael@0: 
michael@0: // Must return b when a == b in case a is -0
michael@0: template <class T>
michael@0: inline
michael@0: const T&
michael@0: XPCOM_MAX( const T& a, const T& b )
michael@0:   {
michael@0:     return a > b ? a : b;
michael@0:   }
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: template <class T>
michael@0: inline
michael@0: const T&
michael@0: clamped( const T& a, const T& min, const T& max )
michael@0:   {
michael@0:     NS_ABORT_IF_FALSE(max >= min, "clamped(): max must be greater than or equal to min");
michael@0:     return XPCOM_MIN(XPCOM_MAX(a, min), max);
michael@0:   }
michael@0: 
michael@0: }
michael@0: 
michael@0: template <class InputIterator, class T>
michael@0: inline
michael@0: uint32_t
michael@0: NS_COUNT( InputIterator& first, const InputIterator& last, const T& value )
michael@0:   {
michael@0:     uint32_t result = 0;
michael@0:     for ( ; first != last; ++first )
michael@0:       if ( *first == value )
michael@0:         ++result;
michael@0:     return result;
michael@0:   }
michael@0: 
michael@0: template <class InputIterator, class OutputIterator>
michael@0: inline
michael@0: OutputIterator&
michael@0: copy_string( const InputIterator& first, const InputIterator& last, OutputIterator& result )
michael@0:   {
michael@0:     typedef nsCharSourceTraits<InputIterator> source_traits;
michael@0:     typedef nsCharSinkTraits<OutputIterator>  sink_traits;
michael@0: 
michael@0:     sink_traits::write(result, source_traits::read(first), source_traits::readable_distance(first, last));
michael@0:     return result;
michael@0:   }
michael@0: 
michael@0: #endif // !defined(nsAlgorithm_h___)